The number 20982
20982 is a composite number with 16 divisors. Its prime factorisation is 2 × 3 × 13 × 269. Divisors (16): 1, 2, 3, 6, 13, 26, 39, 78, 269, 538, 807, 1614, 3497, 6994, 10491, 20982.
Pick any whole number from 1 to 100,000.
How to work it out
- 1
20982 has no famous special property in the usual lists (prime, square, cube, triangular, Fibonacci, palindrome, perfect), but it is still a composite number.
- 2
20982 is composite. Its prime factorisation is
- 3
The divisors add up to 45360; without 20982 itself that is 24378, so 20982 is abundant (24378 is more than 20982). Euler's totient φ(20982) = 6432 numbers up to 20982 share no factor with it.
- 4
The digits of 20982 add up to 21, and repeating that until one digit is left gives the digital root 3. The Collatz sequence (halve if even, else 3n+1) takes 87 steps to reach 1.
LaTeX source of the formulas on this page
\[ 20982 = 2 \times 3 \times 13 \times 269 \]
20982 at a glance
| Property | Value |
|---|---|
| Type | composite |
| Number of divisors | 16 |
| Sum of divisors | 45360 |
| Euler totient φ(n) | 6432 |
| Square | 440244324 |
| Cube | 9237206406168 |
| Square root | 144.851648 |
| Digit sum / digital root | 21 / 3 |
| Collatz steps to 1 | 87 |
| Scientific notation | 2.0982 × |
20982 in other forms
| Form | Value |
|---|---|
| In words | twenty thousand nine hundred and eighty-two |
| Binary (base 2) | 101000111110110 |
| Octal (base 8) | 50766 |
| Hexadecimal (base 16) | 51F6 |
| Base 3 | 1001210010 |
| As time | 20982 seconds = 5 h 49 min 42 s |
Is 20982 divisible by 2 to 12?
| Divisor | Answer | Rule |
|---|---|---|
| 2 | Yes (20982 ÷ 2 = 10491) | A number is divisible by 2 if the last digit is even (0, 2, 4, 6, 8). |
| 3 | Yes (20982 ÷ 3 = 6994) | A number is divisible by 3 if the digits add up to a multiple of 3. |
| 4 | No (remainder 2) | A number is divisible by 4 if the last two digits make a multiple of 4. |
| 5 | No (remainder 2) | A number is divisible by 5 if the last digit is 0 or 5. |
| 6 | Yes (20982 ÷ 6 = 3497) | A number is divisible by 6 if it is divisible by both 2 and 3. |
| 7 | No (remainder 3) | A number is divisible by 7 if double the last digit and subtract it from the rest: the result is a multiple of 7. |
| 8 | No (remainder 6) | A number is divisible by 8 if the last three digits make a multiple of 8. |
| 9 | No (remainder 3) | A number is divisible by 9 if the digits add up to a multiple of 9. |
| 10 | No (remainder 2) | A number is divisible by 10 if the last digit is 0. |
| 11 | No (remainder 5) | A number is divisible by 11 if the alternating sum of the digits is a multiple of 11. |
| 12 | No (remainder 6) | A number is divisible by 12 if it is divisible by both 3 and 4. |
Questions
Is 20982 a prime number?
No. 20982 = 2 × 3 × 13 × 269, so it is divisible by 2.
What are the factors of 20982?
1, 2, 3, 6, 13, 26, 39, 78, 269, 538, 807, 1614, 3497, 6994, 10491, 20982.
What is 20982 in binary?
101000111110110 (hexadecimal 51F6, octal 50766).
What is the square root of 20982?
About 144.8516.
Is 20982 divisible by 3?
Yes. Its digits add up to 21, a multiple of 3.
What is special about the number 20982?
It is a composite number with 16 divisors.